Donald Zackary Greinke (born October 21, 1983) is an American professional baseball pitcher for the Houston Astros of Major League Baseball (MLB).
He previously played for the Kansas City Royals, Milwaukee Brewers, Los Angeles Angels of Anaheim, Los Angeles Dodgers, and the Arizona Diamondbacks.
The Royals selected Greinke in the first round of the 2002 MLB draft, after he won the Gatorade National Player of the Year Award as a high school senior.
After playing in the minor leagues, he made his MLB debut in 2004.
His career was nearly derailed by his battles with depression and anxiety in 2005 and 2006, and he missed most of the 2006 season.
He returned in 2007 as a relief pitcher before rejoining the starting rotation in 2008 and developing into one of the top pitchers in the game.
In 2009, he appeared in the MLB All-Star Game, led the major leagues in earned run average, and won the American League Cy Young Award.